Bangladesh has become the first country in the world to be officially validated for having eliminated visceral leishmaniasis (kala-azar) as a public health problem.
Kala-azar is considered the second deadliest parasitic killer in the world after Malaria.
This milestone results from dedicated efforts and collaboration among various stakeholders.
Bangladesh was successfully validated by the World Health Organisation (WHO) based on the fact that the number of reported cases of visceral leishmaniasis was below one per 10,000 population in each of the country’s sub-districts for at least three consecutive years.
How Bangladesh achieved this milestone?
• Bangladesh, India and Nepal together accounted for 70 per cent of the global burden of the disease between 2004 and 2008.
• In 2005, Bangladesh launched a Regional Kala-azar Elimination Initiative.
• These efforts were accompanied by a Regional Strategic Framework for Elimination of Kala-azar, which focused on early diagnosis, complete case management, integrated vector management, effective disease surveillance, social mobilisation and operational research.
• This was further updated in 2022, with a focus on accelerating and sustaining the elimination status.
• Over the years, research and development efforts led to the introduction of innovative tools such as the rK39 rapid immunochromatographic test and improved treatment options such as miltefosine and liposomal amphotericin B. These tools played a pivotal role in enabling early detection and treatment in remote communities.
• The donation of liposomal amphotericin B (AmBisome), the first-line treatment for kala-azar, by Gilead Sciences Inc, has made an enormous contribution to accelerating the elimination programme in South-East Asia during the past decade. The drug has a high safety profile and an efficacy of over 95 per cent.
• As a result of this synergistic endeavour, new cases of kala-azar have been reduced by 95 per cent across the South-East Asia Region in the past 10 years.
• In 2022, Bangladesh reported only 47 kala-azar cases, and the South-East Asia Region reported 1,069, the historic lowest number.
• Earlier this year, Bangladesh was also validated for having eliminated lymphatic filariasis as a public health problem, marking a significant achievement in the fight against neglected tropical diseases.
Visceral leishmaniasis (kala-azar)
• Leishmaniasis is a neglected tropical disease affecting almost 100 countries including India. It is caused by a parasite called Leishmania, which is transmitted through the bite of sandflies.
• Leishmaniasis is caused by a protozoa parasite from over 20 Leishmania species. Over 90 sandfly species are known to transmit Leishmania parasites.
• It is estimated that 600,000 to 1 million new cases occur worldwide annually.
• Today, more than 1 billion people live in areas endemic for leishmaniasis and are at risk of infection.
There are three main forms of leishmaniasis:
i) Visceral - which affects multiple organs and is the most serious form of the disease.
ii) Cutaneous - which causes skin sores and is the most common form.
iii) Mucocutaneous - which causes skin and mucosal lesion.
• Visceral leishmaniasis, which is commonly known as kala-azar in India, is fatal in over 95 per cent of the cases, if left untreated.
• It is characterised by irregular bouts of fever, weight loss, enlargement of the spleen and liver, and anaemia.
• Kala-azar is a vector-borne disease.
• It is caused by a protozoan parasite Leishmania donovani and transmitted by the female sandfly, Phlebotomus argentipes.
• Sandflies are small insects, about one fourth of a mosquito.
• The parasite primarily infects reticuloendothelial system and may be found in abundance in bone marrow, spleen and liver.
• The global distribution of visceral leishmaniasis is a significant concern, with cases reported across various geographical areas, including East Africa, which serves as another global hub for this disease.
• In kala-azar, diagnosis is made by combining clinical signs with parasitological, or serological tests (such as rapid diagnostic tests).
